A 20-year tale on closing-in behavior in graphic copying tasks: Revisiting Della Sala's findings in new samples of patients with dementia and stroke.

Closing-in behavior (CIB) is characterized by the placement of the graphic copy near (Near CIB) or even on the top of (Overlap CIB) the stimulus to be reproduced. Although CIB has received little attention in the literature, Sergio Della Sala and colleagues made important contributions to the understanding of the phenomenon. They noted that CIB is often observed in Alzheimer's Disease but is also present in other forms of dementia and mild cognitive impairment and stroke; they argued that CIB may reflect a deficit in executive function, rather than working memory, and that the phenomenon occurs more frequently in dual task conditions.

The influence of hand posture on tactile processing: Evidence from a 7T functional magnetic resonance imaging study.

Although behavioral evidence has shown that postural changes influence the ability to localize or detect tactile stimuli, little is known regarding the brain areas that modulate these effects. This 7T functional magnetic resonance imaging (fMRI) study explores the effects of touch of the hand as a function of hand location (right or left side of the body) and hand configuration (open or closed). We predicted that changes in hand configuration would be represented in contralateral primary somatosensory cortex (S1) and the anterior intraparietal area (aIPS), whereas change in position of the hand would be associated with alterations in activation in the superior parietal lobule.

Examining constraints on embodiment using the Anne Boleyn illusion.

Using a mirror box, the concurrent stroking of the lateral side of the fifth finger behind the mirror along with stroking the empty space next to the mirror-reflected hand's fifth finger results in a strong sense of having a sixth finger-the Anne Boleyn illusion. We used this illusion to understand what constraints illusory embodiment. In Experiment 1, we manipulated the anatomical constraints, posture, and stroking of the sixth finger, along with other variants.

Apparent increase in lip size influences two-point discrimination.

Magnified vision of one's body part has been shown to improve tactile discrimination. We used an anesthetic cream (AC) to determine if somesthetic stimulation that alters the perception of the size of one's body would also improve two point-discrimination (2PD). In Experiment 1, application of AC caused an increase in perceived lip size and an improvement in a 2PD.

Searching on the Back: Attentional Selectivity in the Periphery of the Tactile Field.

Recent evidence has identified the N140cc lateralized component of event-related potentials as a reliable index of the deployment of attention to task-relevant items in touch. However, existing ERP studies have presented the tactile search array to participants' limbs, most often to the hands. Here, we investigated distractor interference effects when the tactile search array was presented to a portion of the body that is less lateralized and peripheral compared to the hands.

Peripersonal space around the upper and the lower limbs.

Peripersonal space (PPS), the space closely surrounding the body, is typically characterised by enhanced multisensory integration. Neurophysiological and behavioural studies have consistently shown stronger visuo-tactile integration when a visual stimulus is presented close to the tactually stimulate body part in near space (within PPS) than in far space. However, in the majority of these studies, tactile stimuli were delivered to the upper limbs, torso and face.

Examining central biases in somatosensory localization: Evidence from brain-damaged individuals.

How does the brain localize touch under conditions of uncertainty caused by brain damage? By testing single cases, previous work found mislocalization of touch toward the center of the hand. We investigated whether such central bias changes as a function of uncertainty in somatosensory system. Fifty-one brain-damaged individuals were presented with a tactile detection task to establish their tactile threshold, and a tactile localization task in which they localized suprathreshold stimuli presented at different locations on the hand.

Virtual Reality Treatment Displaying the Missing Leg Improves Phantom Limb Pain: A Small Clinical Trial.

Background: Phantom limb pain (PLP) is a common and in some cases debilitating consequence of upper- or lower-limb amputation for which current treatments are inadequate.

Objective: This small clinical trial tested whether game-like interactions with immersive VR activities can reduce PLP in subjects with transtibial lower-limb amputation.

Methods: Seven participants attended 5-7 sessions in which they engaged in a visually immersive virtual reality experience that did not require leg movements (Cool! ), followed by 10-12 sessions of targeted lower-limb VR treatment consisting of custom games requiring leg movement.

Behavioural and electrophysiological evidence for the effect of target-distractor separation in a tactile search task.

Evidence suggests that the N140cc component of event-related potentials (ERP) observed in tactile search tasks reflects the attentional selection of the target. Here, we investigated whether the target selection processes are affected by the separation between the target and an ipsilateral singleton distractor (singletons delivered to contiguous or non-contiguous fingers of the same hand). In addition, the external distance between search items was varied through posture (splayed or touching fingers).

Virtual image of a hand displaced in space influences action performance of the real hand.

The rubber hand illusion (RHI) demonstrates that under some circumstances a fake hand can be regarded as part of one's body; the RHI and related phenomena have been used to explore the flexibility of the body schema. Recent work has shown that a sense of embodiment may be generated by virtual reality (VR). In a series of experiments, we used VR to assess the effects of the displacement of the virtual image of subjects' hands on action.

Increasing perceived hand size improves motor performance in individuals with stroke: a home-based training study.

Background: Increasing perceived hand size with magnifying lenses improves tactile discrimination and induces changes in action performance. We previously demonstrated that motor skills (tested with grip force, finger tapping, and a reach to grasp tasks) improved when actions were performed with magnified compared to normal vision; twenty-eight percent of 25 participants with stroke exhibited significant improvement on a composite measure of motor performance with magnification as compared to a session without magnification.

Methods: To investigate the potential implications of magnification of vision for motor rehabilitation, we recruited individuals with stroke from the original cohort who exhibited an improvement of at least 10% in grip force and/or finger tapping for a home training protocol.

Bodily sensations in social scenarios: Where in the body?

Bodily states are fundamental to emotions' emergence and are believed to constitute the first step in the chain of events that culminate in emotional awareness. Recent works have shown that distinct topographical maps can be derived to describe how basic and more complex emotions are represented in the body. However, it is still unclear whether these bodily maps can also extend to emotions experienced specifically within social interactions and how these representations relate to basic emotions.

Closing-in Behavior and Parietal Lobe Deficits: Three Single Cases Exhibiting Different Manifestations of the Same Behavior.

Closing-in behavior (CIB) is observed in copying tasks (graphic or gestural) when the copy is performed near or on the top of the model. This symptom has been classically considered to be a manifestation of constructional apraxia and is often associated with a visuospatial impairment. More recent work emphasizes the attentional and/or executive nature of the behavior and its association with frontal lobe dysfunction.

Magnifying vision improves motor performance in individuals with stroke.

Increasing perceived hand size using magnifying lenses improves tactile discrimination and motor performance in neurologically-intact individuals. We tested whether magnification of the hand can improve motor function in individuals with chronic stroke. Twenty-five individuals with a history of stroke more than 6 months prior to testing underwent a series of tasks exploring different aspects of motor performance (grip force, finger tapping, reaching and grasping, and finger matching) under two visual conditions: magnified or normal vision.

Closing-In Behavior and Motor Distractibility in Persons with Brain Injury.

Objective: This study investigates closing-in behavior (CIB), a phenomenon observed in graphic copying tasks when responses encroach upon or overlap the model. The behavior is most common amongst individuals with dementia and amongst pre-school children. We explored the relationship between CIB and the 'distractor effect' in reaching, whereby salient visual stimuli can influence the spatial trajectory of the reach.

Magnifying the View of the Hand Changes Its Cortical Representation. A Transcranial Magnetic Stimulation Study.

Changes in the perceived size of a body part using magnifying lenses influence tactile perception and pain. We investigated whether the visual magnification of one's hand also influences the motor system, as indexed by transcranial magnetic stimulation (TMS)-induced motor evoked potentials (MEPs). In Experiment 1, MEPs were measured while participants gazed at their hand with and without magnification of the hand.

Hand distance modulates the electrophysiological correlates of target selection during a tactile search task.

This study investigated whether the N140cc ERP component, described as a possible electrophysiological marker of target selection in touch, was modulated by body posture. Participants performed a tactile search task in which they had to localize a tactile target, presented to the left or right hand, while a simultaneous distractor was delivered to the opposite hand. Importantly, the distance between target and distractor (hands separation) was manipulated in different experimental conditions (near vs.

Body weight and its association with impulsivity in middle and old age individuals.

Impulsivity, conceptualized as impulsive personality trait, poor inhibitory control and enhanced reward sensitivity, has been strongly linked to obesity. In particular, a disequilibrium between cognitive control and reward sensitivity has been observed in obese individuals in both behavioural and imaging studies. While this issue has been widely investigated in children and adults, it has received little attention in older adults.

Immersive Low-Cost Virtual Reality Treatment for Phantom Limb Pain: Evidence from Two Cases.

Up to 90% of amputees experience sensations in their phantom limb, often including strong, persistent phantom limb pain (PLP). Standard treatments do not provide relief for the majority of people who experience PLP, but virtual reality (VR) has shown promise. This study provides additional evidence that game-like training with low-cost immersive VR activities can reduce PLP in lower-limb amputees.

Closing-in behavior: Compensation or attraction?

Objective: Closing-in behavior (CIB) defines the abnormal misplacement of the copy performance, positioned very closed to or on the top of the model. This symptom is observed in graphic copying by patients suffering from different neurological diseases, most commonly dementia. The cognitive origins of this behavior are still a matter of investigation, and research of the last 10 years has been focused on exploring 2 main accounts of CIB, the compensation and the attraction hypotheses, providing evidence in both directions.

When perception trips action! The increase in the perceived size of both hand and target matters in reaching and grasping movements.

Reaching and grasping movements rely on visual information regarding the target characteristics (e.g. size) and the hand position during the action execution.

A bait we cannot avoid: Food-induced motor distractibility.

Food is so central to humans' life that keeping our mind away from it is not an easy task. Because of its strong motivational value, food cues attract our attention. However, often food is truly not relevant to our on-going activities.

A critical review of closing-in.

When performing complex actions, like graphic copying or imitation of gestures, some patients may perform these actions very close to, or directly on the top of the model. This peculiar behavior, known as closing-in, is the focus of the present literature review, which will provide a critical picture of the research in this field, highlighting the difficulties in defining and assessing closing-in and the contrasting results about the nature and the characteristics of this phenomenon. Most importantly, we will discuss the 2 hypotheses proposed to explain closing-in, namely the compensation and the attraction account, in light of the most recent work.

Do emotions or gender drive our actions? A study of motor distractibility.

People's interaction with the social environment depends on the ability to attend social cues with human faces being a key vehicle of this information. This study explores whether directing the attention to gender or emotion of a face interferes with ongoing actions. In two experiments, participants reached for one of two possible targets by relying on one of two features of a face, namely, emotion (Experiment 1) or gender (Experiment 2) of a non-target stimulus (a task-relevant distractor).

The neural network associated with lexical-semantic knowledge about social groups.

A person can be appraised as an individual or as a member of a social group. In the present study we tested whether the knowledge about social groups is represented independently of the living and non-living things. Patients with frontal and temporal lobe tumors involving either the left or the right hemisphere performed three tasks--picture naming, word-to-picture matching and picture sorting--tapping the lexical semantic knowledge of living things, non-living things and social groups.